Neurotoxicity and Fluoride

Townsend Letter for Doctors and Patients,  May, 2001  by Jule Klotter

• E-mail
• Print
• Link

Dr. Phyllis Mullenix began studying the neurotoxicity of fluoride at the Forsyth Dental Center in 1987, at the request of the center's director, Dr. Jack Hein. Dr. Hein was the scientist responsible for adding monofluorophosphate (MFP) to toothpaste. When Dr. Mullenix and colleagues began investigating fluoride, they did not expect to find any problems. When their first rat experiment indicated that fluoride did indeed negatively affect brain function, they did not believe it. Instead of publishing their results, they repeated the study -- more than once. They tried using more animals, different doses, sexes, ages and methods of administration.

In their 1995 paper titled "Neurotoxicity of sodium fluoride in rats" (Neurotoxicol. Teratol. 17: 169-177,1995), they reported that rats exposed to fluoride as adults exhibited cognitive deficits, and rats exposed to fluoride prenatally showed hyperactivity; "Overall, we concluded that the rat study flagged potential for motor dysfunction, IQ deficits and/or learning disabilities in humans," Dr. Mullenix wrote in a letter to a US Army contractor, BSA Environmental Services.

Even though the fluoride levels that were added to the rats' drinking followed an animal model accepted by dental researchers, critics have claimed that the fluoride levels used in the experiment (75-125 ppm NaF) were too high, and therefore irrelevant. Dr. Mullenix explains that the doses they used produced plasma levels that equal the plasma levels found in humans who drink water containing 5-10 ppm fluoride. Children receiving topical applications of some dental fluoride gels have fluoride plasma levels that are 10 times greater, over an hour, than the rats.

Dr. Mullenix's research is by no means the only evidence of fluoride neurotoxicity. B. Spittle reviewed 60 years of case reports concerning neurological effects of fluoride ("Psychopharmacology of Fluoride: a review" Int. Clin. Psychopharm. 9:79-82, 1994). Dr. Mullenix says that common complaints in these case reports include impaired memory and concentration, lethargy, headache, depression, and confusion. A 1998 study by J.A. Varner and colleagues found that rats whose drinking water contained fluoride (1 ppm) had compromised blood brain barriers that permitted more aluminum to enter the brain ("Chronic administration of aluminum- fluoride or sodium-fluoride to rats in drinking water: alterations in neuronal and cerebrovascular integrity" Brain Res. 784:284-298, 1998). Two studies by J. Luke [(Caries Res. 28:204,1994) & (Fluoride 3 1:S24, 1998)] showed that fluoride accumulates in the pineal glands of animals and of humans, depressing melatonin production.

Dr. Mullenix says that "fluoride exposures today are out of control, well beyond the dose touted as optimum for caries prevention," and that fluoride's toxic effects are amplified by stress, nutritional deficiencies, and interactions with cholinesterase-inhibiting pesticides and toxic metals such as lead and aluminum.

"US Army Medical Command Concerned About Fluoridating" www.nofluoride.com/mullenix_bsa.htm

COPYRIGHT 2001 The Townsend Letter Group
COPYRIGHT 2008 Gale, Cengage Learning